Research On Vehicle Safety Based On GPS Technology

GPS is global positioning system with its continuously higher precision, it not only canbe used for vehicle navigation, but also measure vehicle kinematic parameters used in theactive safety systems. Its installation is simple without initial alignment as traditional IMUunits, further more without integrated error, so it is very easy to conduct field test using GPSmethods, its applications have broad prospects.First this paper discuss the principle of GPS positioning and put forward some methodto improve its precision. In the filed test, a real car is used and its trajectory has beenmeasured, the vehicle kinematic parameters (speed, acceleration, sideslip angel etc) areobtained. Then a bicycle model and3-dof models have been studied, in regard to the thirddegree of freedom: vehicle roll angle, the couple relation between roll angle and the planemovement has been discussed, the relationship between side slip angle,yaw velocity,rollangle and vehicle stability has been studied which can be applied to the vehicle active safetycontrol system.At last a specific prediction model for roll angle has been established, according tohorizontal slope angle, sprung mass and un-sprung mass, a nonlinear second orderdifferential equation is established. Software Matlab has been used to calculate the equation,the maximum roll angle is obtained by numerical calculation which is in accordance withthe test values, which shows that it is an effective model to predict roll angle and it’sreasonable to use GPS method to measure vehicle kinematic parameters. It can be used invehicle active safety control systems...